Charging to 100% and using DC fast charging frequently

[txfab]

EV noob here, just got my MME Premium, standard range, AWD... So far, so happy. I already had a 220V plug in the garage which made the transition quite seamless -- I didn't expect the mobile charger to work so well and fast!
I'm curious how people feel about charging. I had read high level that DC fast charging causes battery to degrade faster over time, so I was prepared to use super chargers sparingly.
Then I was surprised that, additionally to that limitation, Ford recommends only charging to 90% as standard practice. And to only go for 100% charge "when I really need the range for a long road trip". That seemed odd and counter-intuitive to me.
Not to mention it causes a really bad aftertaste from EV marketing if you actually only get the "max range" by risking your battery life long-term!

But then I did some research and it turns out that this article from early 2024
https://insideevs.com/news/707538/recharge-ev-after-every-trip-video/
suggests that "Lithium Iron Phosphate (LFP) can be regularly recharged to 100% without worrying about degradation".

So if my 2024 MME has a LFP battery, why would Ford still tell me to set 90% charging targets? Why wouldn't they limit that recommendation to models with Nickel Manganese Cobalt (NMC) lithium-ion batteries? (my understanding: the Mach-E had NMC before the 2024 model year)

The same article then goes on to quote this study from mid 2023
https://insideevs.com/news/683961/fast-charging-vs-slow-charging-study-ev-range-degradation/
which found that frequent DC fast charging actually does not lead to worse degradation than very infrequent use of it.

My conclusion is, I can fast-charge all I want and I can always charge to 100% (assuming I believe that the "current scientific state" won't be significantly altered by future studies of the same issue). Anyone disagree?

Sponsored

 

[Sikkun]

You can do whatever you want. The battery might degrade slightly faster…but Ford isn’t concerned about it being any faster that it’s a stipulation of your 100k/8 year battery warranty to only charge to x% and not DC charge more than y times.

But if you wan’t to min/max battery health, follow the manuals recommendations.

 

[DugthePug Dad]

Charging to 100% on public DCFC is just rude.

After 80% the charge rate diminishes substantially.

when on public DCFC go to 80% and let the next car charge…

 

[lifebythemile]

Charging to 100% on public DCFC is just rude.

After 80% the charge rate diminishes substantially.

when on public DCFC go to 80% and let the next car charge…

If there's a line up, sure. But if there's 10 of 14 stalls still open, you better believe I'm filling it all the way to 100%.

 

[Sikkun]

If there's a line up, sure. But if there's 10 of 14 stalls still open, you better believe I'm filling it all the way to 100%.

Generally, you will spend more time going form 80-100 (especially 90-100) than just making another charging stop.

 

[lifebythemile]

Generally, you will spend more time going form 80-100 (especially 90-100) than just making another charging stop.

That is true, its usually 30min to 80, then another 30min to 100, but when they recommend charging to 100% at least once per month and I have no home charger, what am I to do?

 

[ChasingCoral]

EV noob here, just got my MME Premium, standard range, AWD... So far, so happy. I already had a 220V plug in the garage which made the transition quite seamless -- I didn't expect the mobile charger to work so well and fast!
I'm curious how people feel about charging. I had read high level that DC fast charging causes battery to degrade faster over time, so I was prepared to use super chargers sparingly.
Then I was surprised that, additionally to that limitation, Ford recommends only charging to 90% as standard practice. And to only go for 100% charge "when I really need the range for a long road trip". That seemed odd and counter-intuitive to me.
Not to mention it causes a really bad aftertaste from EV marketing if you actually only get the "max range" by risking your battery life long-term!

But then I did some research and it turns out that this article from early 2024
https://insideevs.com/news/707538/recharge-ev-after-every-trip-video/
suggests that "Lithium Iron Phosphate (LFP) can be regularly recharged to 100% without worrying about degradation".

So if my 2024 MME has a LFP battery, why would Ford still tell me to set 90% charging targets? Why wouldn't they limit that recommendation to models with Nickel Manganese Cobalt (NMC) lithium-ion batteries? (my understanding: the Mach-E had NMC before the 2024 model year)

The same article then goes on to quote this study from mid 2023
https://insideevs.com/news/683961/fast-charging-vs-slow-charging-study-ev-range-degradation/
which found that frequent DC fast charging actually does not lead to worse degradation than very infrequent use of it.

My conclusion is, I can fast-charge all I want and I can always charge to 100% (assuming I believe that the "current scientific state" won't be significantly altered by future studies of the same issue). Anyone disagree?

Important question: Is your Mach E a 2024 Standard Range?
If not, you have an NMC battery, not an LFP battery.

If you want to learn more about LFP battery care and the difference from NMC, watch this:
https://www.macheforum.com/site/thr...-lfp-battery-degrading-extend-soh-life.38296/

 

[txfab]

Important question: Is your Mach E a 2024 Standard Range?
If not, you have an NMC battery, not an LFP battery.

Didn't realize that but I do have standard range.
Thanks for the clarification and the link to the other thread!

 

[DugthePug Dad]

If there's a line up, sure. But if there's 10 of 14 stalls still open, you better believe I'm filling it all the way to 100%.

I was thinking of EA charging type situations .

Now with Tesla charging being part of the equation, you could have a bunch of chargers available…

I actually charge at home and have not done a DCFC in over a year. Even then it was a 3 charge trip to get my Mach home from Huntington Beach to the Bay Area.

In that trip I was at a EA station with 2 of the 4 chargers out of commission. Yes I got stuck behind 2 cars that charged to 100%. I knew nothing about DCFC and I was there for 2.5 hours start to finish. When I arrived 2 cars were charging and 2 cars waiting, so I thought it wouldn’t be long. I was wrong…

My mindset was to inform a new EV member some charging etiquette

 

[ARK]

Your battery will degrade no matter what. It’s really more a question of how quick depending on the practices you follow. Good practices perhaps get you like 1% or so less degradation per year?

But you can still expect to see a couple or a few percentage battery loss per year. Maybe not initially due to a top buffer Ford has, but definitely once you are going from say Year 2 to Year 3, if you measure it, it will be there.

 

[ChasingCoral]

If there's a line up, sure. But if there's 10 of 14 stalls still open, you better believe I'm filling it all the way to 100%.

Do you have any idea how long you’ll be waiting to charge to 100% at a DCFC?

 

[lifebythemile]

Do you have any idea how long you’ll be waiting to charge to 100% at a DCFC?

Typically I just pull up to one of the 8-12 empty stalls so I never actually have to wait…

If you mean charging, it’s 30min to go from 10-80% and another 30min to go from 80-100%. Just enough time to have dinner at one of the 5 quick serve restaurants in the same parking lot.

 

[ChasingCoral]

Typically I just pull up to one of the 8-12 empty stalls so I never actually have to wait…

No, I mean how long you’ll be waiting for your Mach E to charge all the way to 100%?

 

[txfab]

Your battery will degrade no matter what. It’s really more a question of how quick depending on the practices you follow. Good practices perhaps get you like 1% or so less degradation per year?



But you can still expect to see a couple or a few percentage battery loss per year. Maybe not initially due to a top buffer Ford has, but definitely once you are going from say Year 2 to Year 3, if you measure it, it will be there.

Thanks. I get that, but it seems from those articles / studies that the rate of degradation is not actually different whether I charge to 100% (for LFP battery) or not, or whether I use a lot of fast charging or not.
And that makes a difference for me, especially the 100% full charge part. I normally park on the street... using my charger at night requires "effort". - I guess for most people who pull into a garage every night that doesn't really make a difference... But me, the difference is that I only have to pull into the courtyard where the plug is every 8-10 days, if I charge full every time. Makes driving an EV a whole lot more comfortable!

 

[Womps]

This is right up there with how often should I change my oil on an ice vehicle!. Go by the compute. No, don‘t do that. Every 5,000 miles. No, don’t do that. Every 2,500 miles. No, don’t o that. Go by recommendation in manual. No, don’t do that. Bottom line, it’s your vehicle. Treat it how you want and let the cards fall where they may.

Sponsored